The NodeMcu is an open-source firmware and development kit that helps you to Prototype your IOT product within a few Lua script lines. 

Features

• Arduino-like hardware IO

               Advanced API for hardware IO, which can dramatically reduce the redundant work for configuring and manipulating hardware. Code like    arduino, but interactively in Lua script.

• Nodejs style network API

             Event-driven API for network applicaitons, which faciliates developers writing code running on a 5mm*5mm sized MCU in Nodejs style. Greatly speed up your IOT application developing process.

• Lowest cost WI-FI

              WI-FI MCU ESP8266 integrated and esay to prototyping development kit. We provide the best platform for IOT application development at the lowest cost.

Specification

The Development Kit based on ESP8266, integates GPIO, PWM, IIC, 1-Wire and ADC all in one board.

Power your developement in the fastest way combinating with NodeMCU Firmware!

• USB-TTL included, plug&play
• 10 GPIO, every GPIO can be PWM, I2C, 1-wire
• FCC CERTIFIED WI-FI module
• PCB antenna

For more details visit this link http://nodemcu.com/index_en.html